Recently , a slider with a built-in linear motor is more and more in recent years used in a diversity of instruments including semiconductor manufacturing equipment, assembling machines, measurement instruments and so on. The sliders are also needed compact or downsized and simple in construction while expected to be high in thrust force, accuracy, durability, and convenient to handle and inexpensive. The vertical slider because driven on a vertical shaft is desired to have the movable table in which the weight reduction Is paramount. Moreover, the slider with the built-in movable coil linear motor is required which is reduced in construction, long in stroke length of the table compared with the prior sliders, and further applicable to a variety of usage while convenient to handle.
In a commonly-owned Japanese Laid-open Patent Application No. 2009-219 300, there is disclosed a slider with built-in Linear motors which has a bed of a hooked angular shape in transverse section. The bed is made to have a transverse section less not only in height but also in width thereof and thus made most compact in cross-section. The bed may be determined to have a diversity of the lengths to have various strokes in conformity with uses. The bed is constituted with an elongated rectangular base plate, an upper elongated rectangular plate small in width than the base plate lying in opposition with the rectangular base plate to extend in parallel with the rectangular base plate to provide a predetermined elongated spacing between them, and a side wall connecting integrally opposed side sages of the of the base and the upper plates. With the slider constructed as stated earlier, opposed inside surfaces of the upper plate and the base plate are provided as opposed surfaces of a magnet yoke. Track rails of the linear motion guide unit are installed lengthwise along the edges of the base plate across the area extending out of the opposed inside surfaces. The slider or the linear motion guide unit is fastened to the table moving on the opposed surfaces.